School based exposure to air pollution poses a specific threat to the respiratory health of children, particularly children with asthma. Home indoor air pollution and ambient pollution has been identified as a risk factor for asthma morbidity in children, however, little attention has been paid to the exposures encountered in the classroom. The school is a unique environment in that it is centrally located, has its own traffic patterns, and a high amount of indoor activity leading to resuspension of pollutants. Furthermore, most children are required to spend a large proportion of their time in this environment. This proposal details a five-year project to provide Dr. Jonathan Gaffin, with training and expertise in the assessment of the physical environment with a specific focus on air pollution in the school environment. Dr. Gaffin will study the role of gaseous and particulate air pollution exposure specific to the classroom environment and measure its health effects in an established cohort of inner city children with asthma enrolled in the Allergens in Inner-City Schools and Childhood Asthma study (PI: Phipatanakul). Separately, using geographical information systems (GIS), Dr. Gaffin will integrate the home and school based exposures into a model that will differentiate the independent role of each site in asthma morbidity in inner city children. This novel approach to integrating an exposure from several micro-environments in relation to asthma morbidity will provide a more complete assessment of the individual exposure risk and may lead to more focused and effective interventions. It also provides the foundation for further evaluation of several concurrent factors related to the physical environment in relation to health and disease. Dr. Gaffin will work under the mentorship of Dr. Phipatanakul, an expert in environmental epidemiology and asthma, in addition to an extraordinary team of researchers, including Drs. Diane Gold, Petros Koutrakis, and Brent Coull, who have committed their time, resources, and expertise to facilitate Dr. Gaffin's career development and the successful completion of the proposed project. Dr. Gaffin has a solid foundation in epidemiology, statistics, and research methodology from his Masters of Medical Science degree in clinical research from Harvard Medical School. During this award period, Dr. Gaffin will hone his skills in environmental epidemiology and learn spatiotemporal techniques for environmental assessments and behaviors of elements of the physical environment with a focus on air pollution and childhood asthma. The academic environment created by the mentor, the institution, Harvard University and its affiliates provides a fertile ground for learning and collaborating specific to environmental health, air pollution, and geospatial modeling. Dr. Gaffin will emerge an expert in the field of environmental epidemiology and exposure health effects research, with a unique understanding of the integrated physical environment that will shape him into a highly successful independent investigator.